Loreal preference glam bronze - hair dye 48 hour allergy test - 3 bottles - which one?

[SinisterBumFacedCat]

Any hairdressers or seasoned hair dyers out there? I am probably about to ask a silly question!

I am going to try a new hair dye this week, so I want to do an allergy test before. I've opened up the box and there is no instructions on which product I test. Choice is:

Lightening powder
Developer cream
Lightening cream

Should I try one or all? And once opened don't they have to used immediately? I've googled but Loreal frequently asked questions gave no specific info.

Thank you

I think you need to make up a small amount of the solution (are you meant to mix all three ?)

Are you doing a strand test as well as an allergy test?

Ah that's a good idea!

I don't usually do a strand test, to add the element of surprise